title: Easy and cheap fabrication of ordered pyramidal-shaped plasmonic substrates for detection and quantitative analysis using surface-enhanced Raman spectroscopy.
abstract: In this work we present a simple approach for the fabrication of periodically ordered pyramidal-shaped metallic nanostructures and demonstrate their efficiency as SERS active substrates. Our method for the fabrication of the plasmonic substrate is based on nanoimprint lithography and exploits the thermal properties of two classes of polymers, thermoplastics and hydrogels. During the heating process the thermoplastic polymers will start to melt whereas the hydrogel polymers will form a solid due to the evaporation of water molecules adsorbed during the dissolving process. Using this approach we fabricate highly ordered pyramidal-shaped nanostructures using the texture of a commercial DVD as the initial mold. This technique represents a low-cost alternative to the classical lithography techniques, allowing the fabrication over large areas (~cm(2)) of periodically ordered nanostructures in a controlled and reproducible manner. The SERS efficiency of the fabricated substrate is demonstrated through the detection of urea molecules found in the fingerprint. In addition, due to the periodicity of the pyramidal-shaped structures, the fabricated substrate can be successfully employed to correlate the intensity of the specific SERS peak of urea with the molecules concentration, offering thus the possibility of developing a quantitative SERS renal sensor.
authors.affiliation: Babes-Bolyai University, Interdisciplinary Research Institute in Bio-Nano-Sciences and Faculty of Physics, Nanobiophotonics and Laser Microspectroscopy Center, M. Kogalniceanu Str. 1, 400084, Cluj-Napoca, Romania.
authors.forename: Cosmin
authors.initials: C
authors.lastname: Leordean
authors.forename: Ana-Maria
authors.initials: AM
authors.lastname: Gabudean
authors.forename: Valentin
authors.initials: V
authors.lastname: Canpean
authors.forename: Simion
authors.initials: S
authors.lastname: Astilean
mesh_terms: D049329:Nanostructures / Q000737:chemistry*; D036103:Nanotechnology / Q000191:economics* / Q000379:methods*; D013059:Spectrum Analysis, Raman; D013499:Surface Properties; D014508:Urea / Q000737:chemistry
chemical_list: D014508:Urea